Choosing the right beans

Even the best espresso machine like The Bambino® Plus can't make amazing coffee without the right beans. Specialty coffee roaster Paul Geshos, founder and owner of Mecca Coffee, explains how to select the beans you need to create a café-quality cup of brew. 
First, he gives a primer on bean freshness. Coffee beans are at their peak flavor between 5 and 30 days after roasting. Any sooner than five days after roasting, and the coffee starts to settle, which makes the espresso taste unbalanced and difficult to dial in. Once the beans are older than 30 days, oxidation causes them to lose their flavor, and the delicate aromatics start to degrade. 
He also explains how choosing the right beans depends on the flavor and style of coffee you prefer. Coffee beans with South American origins, like Brazil and Columbia, are generally low in acidity, giving them a medium to heavy body and nutty, chocolatey notes. Coffee beans from Ethiopia and Kenya, on the other hand, have a higher acidity, giving them less bitterness and more floral and delicate notes. 
Stone fruit and citrus are very common flavors, making them the perfect choice for a single-origin espresso or Americano. Paul also describes how to blend multiple varietals, which will build taste complexity.